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Molecular Evolution of the Tre Recombinase
Published on: May 29, 2008
El destino evolutivo y las consecuencias de los genes duplicados
1Department of Biology, University of Oregon, Eugene, OR 97403, USA. mlynch@oregon.uoregon.edu
Science (New York, N.Y.)
|November 10, 2000
Resumen
La duplicación de genes es común, pero la mayoría de los duplicados se pierden rápidamente. Pocos desarrollan nuevas funciones, sin embargo, su silenciamiento puede impulsar la evolución de las especies.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- La genómica es la genómica.
Sus antecedentes:
- La duplicación de genes se considera un motor clave de la novedad evolutiva.
- Las tasas de duplicación génica y la subsiguiente evolución funcional siguen siendo poco conocidas.
Objetivo del estudio:
- Para investigar la frecuencia de los eventos de duplicación de genes.
- Para determinar el destino evolutivo de los duplicados de genes en los eucariotas.
Principales métodos:
- Análisis de bases de datos genómicas de múltiples especies eucariotas.
- Estimación de las tasas de duplicación de genes.
- Evaluación de las presiones de selección sobre los genes duplicados con el tiempo.
Principales resultados:
- Los genes duplicados surgen a una tasa alta (aprox. 0,01 por gen por millón de años).
- La mayoría de los duplicados se someten a una selección relajada, y muchos se vuelven efectivamente neutrales.
- La mayoría de los duplicados genéticos son silenciados dentro de millones de años.
- Los duplicados sobrevivientes están sujetos a una fuerte selección purificadora.
- La nueva evolución funcional en duplicados es rara.
Conclusiones:
- Si bien las nuevas funciones de los duplicados de genes son poco frecuentes, su silenciamiento estocástico puede contribuir a la especiación.
- La duplicación de genes proporciona la materia prima para la evolución, pero su impacto está moldeado por la selección y la dinámica de silenciamiento.
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